This invention relates generally to air conditioning systems and, more particularly, to a drain connection for condensate pans used with evaporator coils in air conditioning systems.
It is common in air conditioning systems to collect and dispose of accumulated condensation at the evaporator coil. This is normally accomplished with the use of a condensate pan or tray which is placed under the evaporator coil and then drained off through a discharge opening to a remote location such as a sewer drain or to the ground outside. Most commonly, the condensate pan is fabricated of a metal material such as steel which, because of the environment, must be painted or coated to prevent rusting. The potential rust problem can be exacerbated by the need for a threaded opening in the pan for connecting to a condensate drainage pipe.
In overcoming the rust problem, it has become desirable to use a moldable plastic material for the condensate pan. In addition to the advantage of being rustproof, the plastic material is characteristically more adaptable to forming in the desired shape to accommodate the particular coil and air flow such that there is relatively little air circulating through the tray to cause a flashing out of the water. In the prior art metal condensate pans, it has sometimes been necessary to provide baffles to prevent such an occurrence.
In certain air conditioning installations, it is required that the condensate pan be connected to a steel pipe to accommodate drainage from the system. This is true, for example, for furnace coils, where the system is installed in a somewhat remote part of the house such as the garage, the basement, a closet, the attic or the like. Typically, this part of the installation is made by a plumber who screws a three quarter inch steel pipe into a female threaded opening in the condensate pan. Since it is a plumbing connection, a standard pipe thread connection (i.e. National Pipe Thread) is normally required by the applicable code. Such a pipe thread is characteristically tapered such that a wedging relationship occurs as the male pipe is screwed into the female opening. Where a steel pipe is screwed into a steel opening, this wedging action occurs until a high torque condition indicates that a secure connection has been made. However, if a steel pipe is screwed into a plastic female coupling, the high torque condition, which the installer has come to expect, does not occur. Rather, the installer is likely to continue screwing in the steel pipe until finally the plastic female coupling breaks.
Another problem with the use of plastic at the connection point is that it is susceptible to corrosive sealers, lubricants and the like. For example, if, as is commonly done, a sealant is placed at the interconnection between the male threads of the steel pipe and a female threads of the female coupling, it may well react with the plastic material and cause damage to the connection.
It is therefore an object of the present invention to facilitate the use of a plastic material for a condensate pan in an air conditioning system.
Another object of the present invention is the provision for connecting a steel pipe to a plastic condensate pan without attendant problems.
Yet another object of the present invention is the provision for protecting a female coupling of a plastic condensate pan from an over-torqued condition when a steel pipe is installed therein.
Still another object of the present invention is the provision for protecting a female coupling of a plastic condensate pan from corrosive materials that may be used when installing a steel pipe therein.
Still another object of the present invention is the provision for an air conditioner condensate pan which is economical to manufacture and extremely functional in use.
These objects and other features and advantages become more readily apparent on reference to the following description when taken in conjunction with the appended drawings.